The present disclosure relates to laser light control devices and image forming apparatuses and particularly relates to a technique for generating a light emission start timing with which emission of laser light based on an image signal is started.
An image forming apparatus includes, as an exposure section, a laser scanning unit configured to irradiate the surface of a photosensitive drum with laser light emitted from a light-emitting part, such as a laser diode, to form an electrostatic latent image. The laser scanning unit includes a BD sensor equipped with, for example, a PIN photodiode, in order to synchronize a reflecting surface of a polygon mirror (rotating polyhedron) with the timing of emission of laser light from the light-emitting part. The BD sensor provided in the laser scanning unit is at a different location from the light-emitting part and the laser scanning unit is configured to generate a BD signal (timing signal) at the time when the BD sensor receives light reflected on the polygon mirror after emitted from the light-emitting part and use the BD signal to generate a light emission start timing with which the light-emitting part starts to emit laser light based on an image signal.